Table 4 Effect of comorbid condition or its treatment on the adverse effects or pharmacokinetics of AEDs

EffectsOlder AEDNewer AED
AED = antiepileptic drug; VPA = valproic acid; CBZ = carbamazepine; OXC = oxcarbazepine; PHT = phenytoin; PB = phenobarbital; GBP = gabapentin; LEV = levetiracetam; TPM = topiramate; ZNS = zonisamide; TGB = tiagabine.
Metabolic disorder may increase risk of hepatotoxicityVPA
Increased risk of hyponatremiaCBZOXC
Measurable increase in free fraction with hypoalbuminemiaPHT VPA
Metabolism affected by renal diseasePBGBP, LEV, TPM
Metabolism affected by liver diseaseCBZ, PHT, VPALTG, ZNS, OXC, TGB